Additional information besides the program counter can be recorded at each interval.
I love the fact that in his question he was talking about the program counter and setting it to something.
Moves to the program counter are allowed and perform jumps.
We fetch the instruction from where the program counter is pointing.
So all the computer does is it loads that 14 bits into the program counter.
Read the code for the next instruction from the cell indicated by the program counter.
For both architectures, r15 is used as the program counter.
And it changed the program counter to a one.
Therefore the program counter is not allowed to fetch from that.
The 16-bit program counter holds the address of the next instruction.